\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Average marginal effect of linear time trend, by subgroup}
\begin{tabular*}{\hsize}{@{\hskip\tabcolsep\extracolsep\fill}l*{4}{c}}
\toprule
            &    US (GSS)         &    US (HRS)         &          UK         &     Germany         \\
            &                     &                     &                     &                     \\
\midrule
Temporary workers&                     &                     &        0.22         &       -0.29         \\
            &                     &                     &      (0.80)         &      (0.71)         \\
\addlinespace
Permanent workers&                     &                     &       -2.37\sym{***}&        1.41\sym{***}\\
            &                     &                     &      (0.48)         &      (0.35)         \\
\addlinespace
Part-time workers&       -0.40         &        0.44         &       -1.53\sym{**} &        1.07         \\
            &      (0.81)         &      (0.47)         &      (0.45)         &      (0.91)         \\
\addlinespace
Full-time workers&        0.30         &        0.88\sym{*}  &       -1.10\sym{**} &        1.09\sym{*}  \\
            &      (0.40)         &      (0.35)         &      (0.34)         &      (0.40)         \\
\addlinespace
New starters&                     &                     &        2.30         &        0.94         \\
            &                     &                     &      (1.86)         &      (0.62)         \\
\addlinespace
Non-new starters&                     &                     &       -1.23\sym{**} &        1.22\sym{**} \\
            &                     &                     &      (0.35)         &      (0.38)         \\
\addlinespace
Males       &        0.50         &        0.83\sym{*}  &       -1.35\sym{***}&        0.92         \\
            &      (0.47)         &      (0.32)         &      (0.35)         &      (0.46)         \\
\addlinespace
Females     &       -0.00         &        0.95\sym{*}  &       -1.08\sym{*}  &        1.38\sym{**} \\
            &      (0.31)         &      (0.39)         &      (0.40)         &      (0.42)         \\
\addlinespace
Over 50 y.o.&        0.51         &                     &       -2.63\sym{***}&        0.99\sym{*}  \\
            &      (0.35)         &                     &      (0.43)         &      (0.42)         \\
\addlinespace
25-49       &        0.15         &                     &       -0.59         &        1.11\sym{*}  \\
            &      (0.45)         &                     &      (0.37)         &      (0.45)         \\
\addlinespace
Under 25 y.o.&        1.25         &                     &       -0.72         &        1.93\sym{**} \\
            &      (0.95)         &                     &      (0.36)         &      (0.57)         \\
\addlinespace
Tertiary degree&       -0.18         &        0.97\sym{*}  &       -0.30         &       -0.06         \\
            &      (0.39)         &      (0.36)         &      (0.31)         &      (0.46)         \\
\addlinespace
No tertiary degree&        0.43         &        0.58         &       -1.72\sym{**} &        1.51\sym{**} \\
            &      (0.38)         &      (0.44)         &      (0.58)         &      (0.46)         \\
\addlinespace
Marginally employed&                     &                     &                     &       -0.04         \\
            &                     &                     &                     &      (2.05)         \\
\addlinespace
Non-marginally employed&                     &                     &                     &        1.08\sym{*}  \\
            &                     &                     &                     &      (0.40)         \\
\midrule
N           &          21         &          12         &          27         &          34         \\
\tabnotes{5}{This table displays the average marginal effect of the linear time trend in a linear regression, where the dependent variable is the AMEs of the year dummies from the main regression specification (Poisson for the UK, logistic for the GSS and SOEP, linear regression for the HRS) with the sample restricted to the subgroup of interest. Standard errors in parentheses. *\textit{p} < 0.05, **\textit{p} < 0.01, ***\textit{p} < 0.001}
